You’ve just acquired a beautiful watercolor painting. The painting is wonderful. Now the question is: how do you frame it in a way that protects it, presents it beautifully, and doesn’t accidentally cause damage that shows up years later?
Framing watercolors is slightly different from framing canvas paintings or photographs. The paper substrate, the water-soluble pigment, and the sensitivity to light and moisture all create specific requirements. Get the framing right, and your painting will look beautiful for generations. Get it wrong, and you risk fading, foxing, buckling, or permanent staining.
Here’s everything you need to know.
The Glass: Your Most Important Decision
The glass (or acrylic glazing) you choose is the single most consequential framing decision for a watercolor painting. Its primary job is protecting the painting from ultraviolet light, which is the main cause of pigment fading.
Museum-grade UV-filtering glass blocks 97–99% of UV radiation and is the gold standard. Tru Vue Museum Glass is the most widely used option — it combines UV protection with an anti-reflective coating that virtually eliminates glare, allowing you to see the painting clearly from any angle. The anti-reflective quality is especially valuable for watercolors, because the soft, luminous quality of the painting is best appreciated without the interference of reflections bouncing off the glass surface.
Conservation-grade UV glass offers UV protection without the anti-reflective coating. It’s a more affordable option that still provides excellent protection. The tradeoff is that you’ll see some reflections on the surface, particularly in rooms with overhead lighting or windows opposite the painting.
Standard glass offers no UV protection. I don’t recommend it for original watercolors. The cost difference between standard glass and conservation-grade UV glass is modest — usually $20–$50 depending on the size — and the investment pays for itself in the longevity of the artwork.
Acrylic glazing (Optium Museum Acrylic, for example) is lighter than glass, shatter-resistant, and available with UV protection and anti-reflective properties. It’s a good choice for very large frames (lighter weight) or high-traffic areas where breakage is a concern. The downside is that acrylic can develop static charge that attracts dust, and it scratches more easily than glass.
The Mat: Space, Protection, and Presentation
A mat serves three important purposes. It creates visual breathing room between the painting and the frame, enhancing the presentation. It physically separates the painting surface from the glass, preventing the paper from touching the glazing — which is critical because trapped moisture between paper and glass can cause mold, adhesion, and staining. And it adds an aesthetic border that allows you to customize the look.
Always use acid-free matboard. Standard matboard contains acids that will migrate into the painting paper over time, causing yellowing, brown staining, and deterioration. Acid-free or museum-grade matboard (sometimes labeled “archival” or “conservation”) is made from purified wood pulp or cotton rag and will not discolor or damage the artwork.
Mat width is a matter of taste, but a common rule of thumb is 2–3 inches of mat border for small-to-medium paintings and 3–4 inches for larger works. Wider mats give the painting more visual presence and can make a small painting feel more substantial. White and off-white are the most popular mat colors for watercolors, but soft grays, warm creams, and pale blues can also work beautifully depending on the painting’s palette.
Double mats — a thin inner mat in a contrasting color beneath the main mat — add a refined, professional touch. A white outer mat with a thin navy, forest green, or warm gold inner mat can subtly accent the painting’s dominant colors.
Mounting: How to Attach the Painting
This is where a lot of well-intentioned framing goes wrong. The painting must be attached to the backing board, but the method matters enormously.
Use acid-free linen hinge tape to attach the painting at the top edge only. This allows the paper to hang freely and expand or contract naturally with changes in temperature and humidity. Two or three small hinges along the top edge are sufficient for most sizes.
Alternatively, use archival photo corners — these hold the painting at its corners without any adhesive touching the painting surface. This is the most reversible mounting method and is preferred by conservators.
Never use regular tape, masking tape, or duct tape. These adhesives contain acids and become brittle over time, staining the paper and becoming nearly impossible to remove without damage.
Never use spray adhesive, rubber cement, or dry mounting. These permanently bond the painting to the backing and are irreversible. If the backing deteriorates or if the painting ever needs conservation treatment, permanent mounting makes the situation dramatically worse.
Never mount the painting tight on all four sides. Paper expands and contracts with humidity. If the painting is rigidly held on all edges, it will buckle, wave, or even tear as it moves.
The Backing Board
Behind the mat and painting, a rigid backing board provides structural support and an additional layer of protection. Use acid-free foam core or acid-free corrugated board. Avoid standard cardboard or foam core that isn’t labeled acid-free.
Some framers add a dust cover — a sheet of kraft paper glued over the back of the frame — to prevent dust and insects from entering. This is a worthwhile addition but make sure the kraft paper is also acid-free.
The Frame Itself
The frame is the most personal choice in the process, and there are no wrong answers as long as the interior components (glass, mat, mounting, backing) are correct.
For watercolors, I tend to prefer frames that are understated enough to let the painting be the focus. Thin, clean-lined wood or metal frames in neutral tones — black, white, natural wood, warm gray — work beautifully for most watercolors. The soft, luminous quality of watercolor can be overwhelmed by ornate or heavy frames.
That said, ornate frames can look stunning with the right painting — a traditional gilt frame on a classical landscape watercolor, for instance, can be magnificent. Trust your instinct and your interior style.
Common Mistakes to Avoid
Putting painting directly against the glass without a mat. Moisture will inevitably form between them. Using acidic materials anywhere in the frame package. Mounting the painting permanently with adhesive. Choosing standard glass with no UV protection. Framing a watercolor that isn’t fully dry. If you’ve recently acquired a painting, make sure it’s had adequate drying time before sealing it behind glass. Using framers who aren’t familiar with works-on-paper conservation standards.
My Recommendation
For most people, the best approach is to take your painting to a professional frame shop and ask for “conservation framing.” Tell them the piece is an original watercolor on paper and that you want UV-protective glass, acid-free matting and mounting, and hinge mounting only. Any reputable framer will know exactly what this means.
If budget is a concern, conservation-grade UV glass (without anti-reflective coating) paired with acid-free matting and hinge mounting is the essential minimum. You can always upgrade to Museum Glass later by having the frame reopened and the glass swapped.
For More on Art Care
Read my companion guide: How to Care for Watercolor Paintings: The Complete Guide
